I lost my book.
I ate chocolate at night.
I reap my mom's paper.

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1.
Alice: I lose my book.
Correct: I lost my book.
Explanation:
*Since it is now your problem, that means you have lost the book. The action happened in the past. Therefore, write lost, not lose.

2.
Alice: I ate chocolate at night.
Correct: No correction

3.
Alice: l ripe mom's paper.
Correct: I reap my mom's paper.
Explanation:
*reap - to cut
*ripe - developed enough and ready to be eaten
Papers cannot be ripe, but reaped.

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Good evening, Alice! Thank you for submitting your homework! You have a few corrections which is alright. Good job! Keep it up!